Los Angeles - Now that Hollywood writers have put down their pens and picked up their picket signs, movie and TV fans – as well as an entire industry – wonder how long the strike will last.

At stake: more TV reruns and fewer films for fans around the world, not to mention an estimated $1 billion in lost revenue for America's entertainment industry if this strike drags on as long as the last major walkout by writers in 1988.

Ostensibly, the crucial sticking point is the writers' demands for a bigger share of the burgeoning DVD market. But the larger issue is how to carve up the revenue pie when technology is changing so quickly that it's impossible to predict how big or even what shape that pie will be.

"So much is unknown about where distribution and entertainment is headed," says Roger Goff, principal of Goff Law Corp., an entertainment-law firm in Redondo Beach, Calif. "And everyone bandies about these huge hypothetical profits that nobody wants to be left out [of]. So it's making the negotiations even harder than usual."

"Usual" in Hollywood is tough enough.

Producers know they must give the same concessions to the directors' and actors' guilds as the writers, which induces extreme caution in every agreement. The last strike lasted five months and cost the industry some $500 million.